NEW YORK -- Fernando Tatis Jr.'s Minor League season is officially over.
The top prospect in a loaded Padres farm system, Tatis will undergo surgery on his left thumb on Tuesday. The 19-year-old shortstop sustained a fracture last week while sliding head first into second base on a steal attempt. He is expected to miss approximately eight weeks, but should recover in time to play either winter ball or in the Arizona Fall League.
Tatis is rated as the No. 3 overall prospect in baseball according to MLB Pipeline, and was hitting .286/.355/.507 at Double-A San Antonio this season. As an organization, the Padres aren't worried about any long-term effects from the injury.
"Ultimately, guys that have this surgery come back and their range of motion is good, their strength is good," said Padres general manager A.J. Preller. "It's more of a hiccup than anything else."
Given Tatis' recent success, the timing of the injury isn't ideal. It rules out a potential September callup, which seemed a distinct possibility after his two-hit showing at the Futures Game last week.
But the Padres aren't concerned with the development time that Tatis will lose. He played deep into the Double-A postseason last year, then played for Estrellas de Oriente in the Dominican Winter League. Barring any setbacks, he'll almost certainly be back on the field this fall and/or winter.
"In the last two years, he's played a ton of baseball, gotten a ton of games, gotten a lot of at-bats," Preller said. "Instead of two complete years, it's like a year and four-fifths. Ultimately, it's OK."
The Padres maintain that Tatis' injury won't shape their offseason plans at shortstop. With Freddy Galvis' contract set to expire after the season, they don't have any long-term, big league-ready options.
Tatis, one team source said, is expected to compete for a starting job during Spring Training next season. Still, the Padres almost certainly won't treat Tatis like Galvis, who has started at short in every game this season. It's likely they move to sign a veteran who can compete with Tatis and bridge the gap if more development time is needed. Galvis will certainly be an option for that role.
When asked, Preller declined to look that far ahead. But he was quick to praise Tatis for his 2018 performance. The young shortstop struggled out of the gate, posting a .177/.231/.333 slash line through April.
After that month, Tatis responded in a big way. Since the start of May, he is hitting .327/.404/.571 with 13 homers. It was a successful season -- even if it was ultimately cut short.
"He was one of the youngest players in the league," Preller said. "We challenged him, and I think he responded to the challenge. In baseball you have to respond to failure. He's shown he can be given a challenge, then come through with flying colors. ... He was able to take his game to a different level. There were a lot of positives from this year that he can still take into the offseason."
Margot returns from wrist sprain
Center fielder Manuel Margot was back in the Padres' lineup, hitting seventh, on Monday night vs. the Mets at Citi Field. Margot hadn't played since Friday, when he sprained his left wrist making a diving attempt at a fly ball in Philadelphia.

It was an ugly injury in which Margot's wrist snapped backward when his glove hand collided with the ground. But postgame X-rays were negative, and all things considered, a two-game absence was the best-case scenario.
Brewer lands on DL
Righty reliever Colten Brewer was placed on the disabled list Monday with a left oblique strain. He sustained the injury while pitching to the Phillies' Rhys Hoskins in the ninth inning of Sunday's doubleheader nightcap. Brewer faced two more hitters, striking both out. But he reported the injury afterward, and the soreness has only gotten worse since.
There's no timetable for Brewer's return, but the Padres expect him to be out for at least a couple of weeks. In four appearances this season, Brewer has allowed four runs (though all four were unearned) over three innings.
The move allowed for left-hander Joey Lucchesi to be recalled and start on Monday night in New York.